Microwave Ablation of Small Hepatic Metastases Using MR Guidance and Monitoring: Clinical Safety and Efficacy

Abstract

Background

To evaluate the technical success and clinical safety of magnetic resonance (MR)-guided microwave ablation (MWA) of small hepatic metastases.

Materials and Methods

Institutional review board approval and informed patient consent were obtained. A retrospective analysis of the patient data revealed 50 patients with small hepatic metastases (34 men, 16 women) who underwent MWA under MR guidance and monitoring. After the procedure, the intervention-related complications were classified according to the Common Terminology Criteria for Adverse Events (CTCAE) and Society of Interventional Radiology (SIR) classification system. Furthermore, the overall survival (OS) and local tumor-free survival (LTP) of the patients were analyzed.

Results

The patients who underwent MR-guided MWA achieved technical success. The mean energy, ablation duration per tumor, and procedure duration were 55.3 ± 9.4 kJ, 11.7 ± 5.6 min and 89.5 ± 30.9 min, respectively. Most adverse events and complications were CTCAE grade 1 or 2 or SIR classification grade A or B. The 1-, 2-, and 3-year local tumor progression (LTP) rates were 65.9%, 31.5% and 18.5%, respectively, with a mean LTP of 19.216 months (95% CI: 16.208, 22.224); and the 1-, 2- and 3-year overall survival (OS) rates were 81.8%, 60.8% and 44.7%, respectively, with a mean OS of 26.378 months (95% CI: 23.485, 29.270). Multivariate Cox’s regression analysis further illustrated that tumor location (challenging locations vs ordinary locations) and the anesthesia (general anesthesia VS local anesthesia) were important factors affecting LTP and OS.

Conclusion

MR-guided MWA can successfully treat small hepatic metastases with potentially favorable safety and technical efficacy.

Keywords:

• microwave ablation
• magnetic resonance imaging
• liver tumors
• tumor ablation
• hepatic malignancies

Acknowledgments

We would like to thank the patients and all employees of the First Affiliated Hospital of Zhengzhou University for interventional radiology. Thanks to Ms. Chen Xinyue from CT collaboration NE Asia, Siemens Healthcare, Beijing, China, contributed strong technical support as well as language polish to this article.

Abbreviations

MR, Magnetic Resonance; MWA, Microwave ablation; RFA, Radiofrequency ablation; CTCAE, Terminology Criteria for Adverse Events; mRECIST, Modified Response Evaluation Criteria in Solid Tumors; LTP, Local tumor progression; OS, Overall survival; SIR, Society of Interventional Radiology.

Data Sharing Statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Ethics Approval and Consent to Participate

This study protocol was approved by the institutional review board of the First Affiliated Hospital of Zhengzhou University. The study was conducted in accordance with the ethical principles laid down in the Declaration of Helsinki. Written informed consent was obtained from all patients before treatment.

Consent for Publication

Not applicable.

Disclosure

The authors declare that they have no competing interests.